Steps to reproduce:

1. Read printer SNMP OID prtMarkerSuppliesDescriptionChanges and  get from a Russified HP printer a set of several elements in Unicode. For example, one of them: D0 9C D0 BE D0 B4 D1 83 D0 BB D1 8C 20 D1 81 D0 B1 D0 BE D1 80 D0 B0 20 D1 82 D0 BE D0 BD D0 B5 D1 80 D0 B0 20 48 50 20 43 45 32 35 34 41 00  I connect JavaScript in preprocessing and get - Модуль сбора тонера HP CE254A. All is right. Next, turn on LLD and try to convert {#SNMPVALUE} to a string. The Template SNMP Printer is used. First step is JSONPath = $[:]{# SNMPVALUE}
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4. Result: 

   [error] => Preprocessing failed for: [{"{#SNMPINDEX}":"1.1","{#SNMPVALUE}":"D0 A7 D0 B5 D1 80 D0 BD D1 8B D0 B9 20 D0 BA D0 "},{"{#SNM... 1. Failed: cannot extract value from json by path "$[:]{#SNMPVALUE}": unsupported construct in jsonpath starting with: "{#SNMPVALUE}"
   

5. It can be seen from the text that: 1. not all the value obtained from the request was saved in {#SNMPVALUE}, 2. for some reason, JSONPath = $[:]{# SNMPVALUE} does not work

Result:
See screenshot...
See log file...
See memory dump...
Expected:
See screenshot....
See attached patch file...